1. Field of the Invention
The invention relates to wheelchairs. More particularly, the invention relates to portable wheelchairs designed to be collapsed into a storage configuration.
2. Description of the Prior Art
Conventional wheelchairs generally include a seat, a backrest, and a footrest rigidly secured to a pair of wheels. These wheelchairs are collapsed by pushing the wheels toward each other while the seat, backrest, and footrest collapse to a certain extent. As is well known to individuals familiar with these wheelchairs, they are generally very cumbersome to transport and/or store, even when they are in their collapsed state. In addition, these wheelchairs are often very heavy and do not collapse into a convenient, compact arrangement. Specifically, conventional wheelchairs collapse such that the left and right wheels move toward each other. The collapsed wheelchair is, therefore, narrower than the fully expanded wheelchair, but the support structures associated with the wheelchair continue to extend outwardly beyond the circumference of the wheels. These extending structural elements make it difficult to store the collapsed wheelchair.
Advances in design techniques and materials have made the development of lightweight, portable wheelchairs possible. The recent development of lightweight, portable wheelchairs has been met with great anticipation by individuals confined to wheelchairs, since these individuals were previously forced to accept and deal with the functional limitations of heavier, more cumbersome wheelchairs.
Unfortunately, recent developments in lightweight wheelchairs have produced relatively complex wheelchairs. While these wheelchairs are lighter and less cumbersome than prior wheelchairs, they are often difficult for wheelchair users to operate as a result of their complex designs. For example, U.S. Pat. No. 5,261,684, to Soto, discloses a portable, lightweight wheelchair, which includes a seat and footrest secured between a pair of spokeless wheels. The wheelchair is stored by disassembling the wheels, seat and footrest. The disassembly and assembly process is, however, complicated. Furthermore, the assembly process relies upon a variety of complex connections to retain the wheelchair in its assembled configuration. Once the wheelchair is disassembled for storage, the user must handle many pieces before the wheelchair is ready to be stored away. Similarly, after retrieving the wheelchair from storage, the user must assemble the variety of pieces before the wheelchair user is ready to employ the wheelchair.
In view of the limitations of prior wheelchairs, it is apparent that a need continues to exist for a lightweight, portable wheelchair that is readily adapted for storage and/or use. Such a wheelchair should exhibit excellent stability, while permitting a wheelchair user to collapse the wheelchair with limited difficulty and subsequently prepare the wheelchair for use when the user needs the wheelchair again. The present invention provides such a wheelchair.